Reinforcing steel couplers or connectors are known for attaching the abutting ends of rebar sections together. Such connectors are commonly utilized to interconnect adjoining precast structural members such as beams and columns in the building construction process. The use of such connectors has been found to be generally preferable to lap splicing wherein the rebar members are positioned such that they overlap and are then welded together or attached to one another by tieing with heavy gage wire.
For example, to attach a horizontal beam to a vertical column, the beam is positioned as desired proximate the column such that first rebar members extending from the beam are almost in abutting relationship with complimentary second rebar members extending from the column. A small gap is present at this time between the first and second rebar members. First and second coupler or attachment members are threaded onto each pair of corresponding first and second rebar members, respectively. The first and second attachment members are threaded on the inside to receive the first and second rebar members and are threaded on the outside to screw into a common or third member.
Next, the third member, comprising a threaded sleeve, is positioned intermediate the first and second attachment members and then rotated such that the first and second attachment members screw thereinto, in a turnbuckle-like fashion. Thus, as the sleeve is rotated, the first and second attachment members, attached to the first and second rebar members, respectively, are drawn together into abutting relationship.
Alternatively, the threaded ends of the first and second rebar members themselves are screwed directly into the sleeve as the sleeve is rotated in a turnbuckle-like fashion. One example of such a coupler is the Lenton Tapered Threaded Splicing System manufactured by Lenton of Erico of Solon, Ohio.
Alternatively, in the prior art a metal filled splice may be utilized to interconnect two rebar members. The ends of each rebar member are received within a common housing and the housing is then filled with molten metal. One example of such a metal filled splice is the Cadweld Splice manufactured by Erico of Solon, Ohio.
As a further alternative in the prior art, the ends of two rebar members may be received within a common housing which is then filled with a cementitious filler, i.e., grout. One example of such a device is the Interlok Splicing System manufactured by Erico of Solon, Ohio.
All such contemporary connectors provide positive mechanical interconnection of the abutting complimentary rebar members. Such interconnection is completely rigid and does not accommodate relative longitudinal motion of the rebar members. Consequently, relative motion of the joined structural members, i.e., beams and/or columns, is likewise not facilitated.
As such, although contemporary reinforcing steel couplers or connectors are generally suitable for their intended purposes, they possess inherent deficiencies which detract from their overall effectiveness in building construction. It is therefore desirable to provide an alternative reinforcing steel coupler or connection which accommodates a degree of longitudinal motion of the abutting rebar members and consequently likewise accommodates a degree of relative movement of the joined structural members, i.e., columns and/or beams. It is further desirable to provide a coupler or connector which dissipates a substantial portion of the energy causing such movement so as to mitigate damage caused by earthquakes and the like.